Einstein's Special Theory of Relativity was proposed a little over
a hundred years back. It remained a bedrock of twentieth century
physics right up to Quantum Field Theory. However, the failure
over several decades to provide a unified description of
Electromagnetism and Gravitation or alternatively, Quantum Theory
and General Relativity has finally lead researchers to abandon the
differentiable spacetime manifold on which all of the above was
based. In the most recent approaches we consider a spacetime that
is discretized or is noncommutative. This immediately leads to
corrections to the Special Theory of Relativity, more specifically
to Lorentz Symmetry. It is quite significant that there are
observational indicators, particularly in ultra high energy cosmic
rays which suggest that such corrections are indeed there. We
examine the whole issue in this paper.